Table 1.

Data cleaning criteria, number of respondents with unclear results, and action taken.

Variable	Criteria	Respondents	Result
Age	Respondents in the USA aged <22 years	n = 3	Removed from sample
Progression status	Respondents without a response to progression (yes/no), but a response for date of progression	n = 13	Progression marked “unknown”
	Respondents with a “yes” response to progression, but no response for date of progression	n = 34	Progression marked “yes”
	Respondents with a “no” response to progression, but with response for date of progression	n = 42	Progression marked “unknown”
Other therapy	Respondents without a response to other GBM therapy (yes/no), but a response for date of initiation	n = 6	Other therapy marked “unknown”
	Respondents with a “yes” response to other GBM therapy, but no response for date of initiation	n = 79	Other therapy marked “yes”
	Respondents with a “no” response to other GBM therapy, but with response for date of initiation	n = 7	Other therapy marked “unknown”
Time since diagnosis	Respondents with a negative value for time since diagnosis	n = 1	Time since diagnosis marked “unknown”
	Respondents with diagnosis year prior to date of birth	n = 1	Time since diagnosis marked “unknown”
Time on TTFields	Patients with >9 years of time on TTFields	n = 5	Time on TTFields marked “unknown”
	Patients with time on TTFields greater than or equal to time since diagnosis	n = 26	Time on TTFields marked “unknown”

TTFields, tumor treating fields.